The small floods that submerge roads and sometimes enter homes along Louisiana's coast could become more than an occasional headache. A new study suggests that the frequency of "nuisance flooding" around the Gulf of Mexico will double every decade thanks to small rises in sea level.

In lower latitudes, the flooding will be worse. The tropics, including South America and Africa, will experience a doubling of extreme flooding due to sea level rise, said Sean Vitousek, lead author of the study published in the Scientific Reports journal this week.

On the Louisiana coast, hurricanes, rather than sea level rise, will continue to pose the biggest flood danger. The same is true for the Caribbean Sea and the East Coast. "But the smaller floods are something to worry about, especially as they happen with more frequency," said Vitousek, a coastal hazards researcher at the University of Illinois at Chicago.

Nuisance flooding can degrade drainage and sewer systems, contaminate drinking water supplies, damage buildings and disrupt transportation and commerce. Decades ago, it was powerful storms that caused such problems.

"But due to sea level rise, more common (storm) events are now more impactful," wrote National Oceanic and Atmospheric Administration scientists in a 2015 report on nuisance flooding. The agency said small coastal floods have been happening two or three times more frequently than just 20 years ago.

The ways that sea level rise affect flooding are varied. Rising sea levels alter water depths, the generation of waves and the interactions between waves, tides and storm surges - all of which can trigger coastal flooding.

Low-lying coastal Louisiana is particularly susceptible to sea level rise. While ocean waters swell, much of the land sinks, partly due to the natural settling of river sediments under which much of southeast Louisiana is built. This combination of sea rise and sinking land is known as relative sea level rise.

Vitousek's research is the first to consider large waves and storm surges as factors in pushing rising sea levels into flood-prone coastal areas. Past predictions were limited to tide gauge data. Vitousek combined tidal, wave and storm surge data to create his predictive model.

The climate change-induced melting of ice caps is expected to increase global sea levels by 4 to 8 inches by 2050. For the tropics and other parts of the world, that will mean a doubling of extreme flooding events, impairing the economies of coastal cities and the livability of low-lying Pacific island nations, the study says.

"The takeaway is that it doesn't take much sea level rise - just 5 to 10 centimeters - to double the frequency of floods," Vitousek said.